1. Technical Field
The present invention relates to a printing apparatus that includes a transport portion transporting a medium such as paper, a printing head performing printing on the transported medium, and a medium detection device capable of detecting a side edge of the medium in a width direction intersecting with a transport direction.
2. Related Art
In the related art, a printing apparatus that has a transport portion transporting a medium such as paper and a printing head performing printing on the medium has been widely known as one example of this type of printing apparatus (for example, JP-A-2001-287405 and the like).
For example, in JP-A-2001-287405, disclosed is a serial type printing apparatus (serial printer) that includes a paper width detection device (one example of a medium detection device) detecting the width of paper in a position upstream of a printing unit in the transport direction of paper (one example of a medium). This printing apparatus includes a carriage and two sensors (a right side detector and a left side detector). The carriage includes a printing head that moves by driving of a motor in a paper width direction (main-scanning direction) orthogonal with respect to the transport direction of the paper and performs printing. The two sensors are disposed in a position upstream of the printing head of the carriage in the transport direction. While the carriage moves in the paper width direction, the right side detector detects the right side edge of the paper, and the left side detector detects the left side edge of the paper.
The paper width detection device disclosed in JP-A-2001-287405 is disposed in the carriage that is movable in the main-scanning direction in order to perform printing in the serial printing type printing apparatus. Thus, printing apparatuses that do not include a printing carriage, for example, a line printing type printing apparatus (line printer), cannot employ a configuration in which a sensor is disposed in the printing carriage. In addition, in the case of separately attaching a device that can detect both side edges of a medium having the maximum width predetermined in the printing apparatus, a problem arises in that the size of the printing apparatus in the width direction may be increased. This type of problem is common to a serial printing type printing apparatuses as well in a case where a configuration in which a sensor is included in the printing carriage as in JP-A-2001-287405 is desired to be avoided in order to prevent a decrease in detection accuracy due to a sensor being stained with ink.